1. Field of the Invention
The invention relates to a roller device, more particularly to a roller device for a conveyer that is highly weather-resistant.
2. Description of the Related Art
Referring to FIG. 1, a currently available conveyer includes a support frame unit 1, a plurality of roller devices 2 mounted on the support frame unit 1, and a conveyor belt 3 supported by the roller devices 2. The support frame unit 1 has a bottom frame 101, and a plurality of support rods 102 fixed to the bottom frame 101. Each of the roller devices 2 has a spindle 201 positioned between two support rods 102, a roller body 202 sleeved on the spindle 201, two bearing assemblies (not shown) sleeved between the spindle 201 and the roller body 202, and two anti-leak units (not shown) sleeved respectively on outer sides of the bearing assemblies.
Although the aforementioned conveyer utilizes the anti-leak units to prevent dust and moisture from entering the roller body 202 of each roller device 2 so that the service life of the bearing assemblies is ensured and the normal operation of the conveyor belt 3 is maintained, when the conveyer is installed outdoors for use in conveying, for example, sandstone, salt, ore, etc., because of the bad environmental conditions that may be present, such as those encountered in seaside areas, where acid-base elements are present, two ends of the spindle 201 that are exposed on an outer portion of each roller body 202 are easily damaged due to corrosion, so that the service life of the spindle 201 is shortened.
U.S. Pat. No. 6,206,182 discloses a co-injected labyrinth and contact seal for an idler roller assembly for a belt conveyor background of the invention. The idler roller assembly includes a fixed shaft, a roller mounted for rotation about the shaft, and a housing mounted in each end which hub portion is disposed adjacent the housing. However, two opposite ends of the fixed shaft are exposed from the hub portion, and are thus easily damaged due to corrosion, so that the service life of the fixed shaft is similarly shortened.